...speaking of ducks, I took on duck eggs to hatch for a man. He provided me with about 45 of the nastiest eggs I have ever seen. I washed them and sprayed them with a weak Betadine solution.
At day 14, I candled and threw out all but 21 that all went into the hatcher on day 22 because they had started to pip. The first four pipped and zipped and popped out just fine. Several pipped and stopped, some didn't pip at all. I gave them about 36 hours and started to help. I managed to get 6 live ducklings out by helping, but one of the first four died while I was at work. Two of the ones I helped out have deformaties on the back of their heads. They look like the ones with the feather tufts, but they have other issues as well.
Is this typical of ducks? How likely is it an issue with incubation if there were also chicks cooking at the same time (which produced my best hatch ever!?)